To treat stenosis—the narrowing of a bodily passage—physicians frequently dilate the bodily passage using a balloon catheter. For example, when functioning normally, the trachea allows air to pass from the pharynx and larynx to the lungs. However, when the trachea becomes obstructed, for example when a stricture forms within the trachea wall, the volume of air that can pass to and from the lungs is reduced. This results in respiratory complications, such as difficulty breathing, breathlessness, coughing, and wheezing.
To treat these conditions, physicians sometimes perform balloon dilation—the dilation of a bodily passage using a balloon catheter—to unblock the passage. Conventional dilation procedures advance a balloon catheter to a point of treatment and move the balloon to an inflated configuration to effectuate dilation and unblock the obstructed passage. However, these procedures are complicated due to the application of axial forces on the tissue forming the obstruction as the balloon catheter is advanced toward the point of treatment. This can result in damage to the tissue of the passage wall, which increases the trauma experienced by the patient during treatment. These procedures are also complicated due to the passage becoming blocked during dilation of the obstruction. For example, when treating a stricture formed in the wall of the trachea, the balloon catheter obstructs the airway when it is in the inflated configuration and prevents oxygen from passing to the lungs. Therefore, conventional procedures require the balloon to be inflated for short periods of time and then deflated multiple times so that oxygen saturation levels can be maintained, or restored, during treatment.
Therefore, a need exists for improved medical devices and methods for providing access to a bodily passage during dilation.